Television apparatus



Sept. 14, 1937. w. H. PECK TELEVISION APPARATUS Filed Oct. 5, 1934 5Sheets-Sheet 1 INVENTOR MW/km /7. ec/{ Sept. 14, 1937. w. H. PECK2,092,353

' TELEVISION APPARATUS Filed Oct. 5, 1934 5 Sheets-Sheet 2 6h Fi o l I Ial 88 u f IINVENTOR .4 MW/am H 604 0%,WmQ,

ATTORNEYS Sept. 14, 1937. w. H. PECK TELEVISION APPARATUS Filed Oct. 5,1934 5 Sheets-Sheet 3 BY 0 9%, WM a ATTO R N EYS Sept. 14, 1937. w. H.PECK 2,092,853

TELEVIS ION APPARATUS Filed Oct. 5, 1934 5 Sheets-Sheet-4 INVEIINTORM/fiam ff Peck ATTORNEYS Sept. 14, 1937.

w. PECK TELEVISION APPARATUS Filed Oct. 5, 1934 5 Sheets-Sheet 5 INVENTRBY WI Dw L-AJ-Q-- ATTORNEYS Patented Sept. 14, 1937 UNITED STATES PATENTOFFICE Application October 5,

4 Claims.

This invention relates to television systems, to televisiontransmitters, and more particularly to television transmitters forscanning the areas of a strip of photographic film, such as a reel ofmotion or talking picture film.

An object of the invention is to provide an improved form of televisionscanning apparatus for creating in an electrical circuit, a currentvarying in amplitude in correspondence with the variations in opacity ofcontiguous elementary areas constituting in aggregate the entirephotographic area of a strip of film.

A feature of the apparatus resides in the fact that it employs no gearsor intermittent drive. The apparatus is thus of extremely simpleconstruction as compared to known systems of the same character. Movingparts are reduced to a minimum. For both of these reasons the operationis noticeably quiet and free from vibration.

The apparatus is adapted to scan simultaneously both the sound track andthe picture portions of talking picture film. This necessitatesmaintaining great uniformity of film feed at the point of scanning toprevent distortion in the process of scanning such as is particularlynoticeable in the reproduced sound effects. In accordance, therefore,with a. further object of the invention the requisite uniformity of filmfeed is secured by passing the film strip at the point of scanning overrelatively massive idling rollers mounted on ball bearings, the housingsof which are packed with a viscous medium, such as a heavy high heatgrease in contact with relatively large areas of the fixed and movablebearings races. The mass of the rollers is sufiicient to maintain themrotating uniformly despite momentary fluctuations in tension in the filmdue, for example, to variations in speed of the driving sprockets. Theviscous packing on the other hand provides a slight braking action whichmaintains the film under proper tension as it passes over the idlers.

In its essentials the apparatus of the invention employs a tubularstationary shaft and a parallel motor driven rotatable or driving shaft.The tubular shaft has formed in its cylindrical surface, a pair ofaxially displaced scanning apertures, one of which forms part of thepicture scanning mechanism, while the other aperture is similarlyutilized for scanning the sound track of the film.

The picture and sound track portions of the film are separately scannedalthough simultaneously, by feeding the film a plurality of times fromthe driving shaft about the tubular shaft.

1934, Serial No. 747,057

To this end the tubular shaft is provided with a plurality of theaforesaid spaced idling rollers coaxial with the shaft and in viscousbearing contact therewith as stated. One pair of rollers is so disposedthat the film in one passage about the shaft has its picture portion fedpast the picture scanning aperture disposed between the rollers. Asecond pair of rollers axially displaced from the first feeds the soundtrack of the film in a second passage about the shaft past the soundtrack aperture therein.

The film, supplied from a first reel and rewound on a second reel, isdriven by sprockets keyed to the driving shaft, the sprockets havingteeth adapted to engage the perforations along the edge of the film asit is fed successively from the driving to the tubular shaft.

Scanning of the picture and sound track portions of the film isaccomplished by a pair of optical systems, each employing a lightsource, a photoelectric element together with suitable light reflectingand focusing elements for directing a scanning beam from the propersource through the film onto the associated photoelectric element. Thephotoelectric elements are conveniently mounted within the tubular shaftbeneath the picture and sound apertures respectively.

A fixed optical system, i. e., one employing no moving parts, sufficesfor scanning the sound track. For this purpose the light source andfocussing elements are disposed in a tubular housing external to thetubular shaft and positioned to focus a beam of constant intensity onthe film at the sound aperture.

A somewhat similar arrangement is utilized for scanning the picture,with the exception that in this instance, the scanning beam is variablydeflected transversely of the film by a light refleeting rotatablescanning member. This is conveniently accomplished in accordance withthe invention, by keying the rotatable scanning member to the shaft of aseparately driven motor having its axis of rotation in a planeperpendicular to the axis of the tubular shaft.

The rotatable scanning member may be of a known construction employing amultiplicity of mirror elements suitably disposed at proper in clinationabout the periphery thereof for causing the scanning beam to traversethe film in a succession of contiguous transverse paths. Prefarably,however, the scanning member employs the principles of constructiondescribed and claimed in my copending application Serial No. 601,495,filed March 28, 1932, wherein the scana ing preferably anterior surfacesof spherical contour, and plane posterior surfaces which are mirrored.These lens elements are so disposed about the periphery of the rotatablemember that the scanning beam impinges normally on the curved anteriorsurface, of each lens while it intercepts the beam, the beam beingtotally reflected internally at the plane mirrored posterior surface ofthe lens normally back throughthe' anterior surface. The lens thusserves the dual role of variably deflecting the beam for scanning and ofdistortionlessly focussing the beam at the film surface, all as is fullydescribed in my said copending application and referred to hereinafter.v

In the process of scanning'with the apparatus and subsequent recreationof the image with receiving apparatus, the recreated image may not beproperly framed on the screen. To eliminate this defect the stator ofthe motor which drives the film feed is, in accordance with theinvention, so mounted as to be rotatable within proper limits by amanually actuated worm gear. Thus by simply rotating the stator of thedriving motor, an image thrown on the screen of a receiving apparatusmay be vertically displaced up or down on the screen until it isproperly framed.

Referring to the drawings: Fig. 1 is a front elevation of apparatus inac cordance with the invention for scanning the picture-and sound trackof. talking picture film.

Fig. 2 is a rear elevation of the apparatus, and Fig. 3 a plan view asviewed from above and facing to the right in Fig. 2. a 'Fig. 4 is anenlarged plan view of the film feed mechanism for scanning 'as viewedfrom above and facing to the right in Fig. 1., Figs. 5 and 6 are at 55and 66 respectively of Fig. 4. a

Fig. '7 is a'plan view of the scanning disc as viewed from below in Fig.6 with the hemispherical housing removed.

Fig. 8'is a section at 88 of Fig. 6.

Figs. 9 and 10 are sections at 99 and lll-l0 of Fig. 6. a

Fig. 1 1 is a section at IIII of Fig. 4, and'Fig. 12 a horizontalsection at I2I2 of Fig. 11.

Fig. 13 is a diagrammatic showing of the optical systems for scanning ofthe picture and sound track of the film. V Referring to the drawings theentire scanning apparatus is mounted on a panel I supported by a standZ. The strip of film 3 to be scanned is unwound from a reel 4 andrewound on a second reel 5, the reels being housed in a' standard mannerin drum casings 6 and I respectively carried by panel I and providedwith hinged covers as shown for affording access to the reels. Thetakeup reel 5 is driven from a motor 8, Fig. 2, by means of belt 9passing over pulleys I0 and II keyed to the motor and reel shaftsrespectively.

For purposes of scanning, the film, in passing 7 from reel 4 to reel 5,is fed a plurality of times about a 'pair of parallel shafts I2 and 93,Fig. 4.

To this end shaft I2, which is a tube afiixed to and. projecting frompanel I, has arranged co-' axial therewith a plurality of axially spacedfilm idling rollers I 4, I5, I6, I! rotatably mounted on shaft I2 by theinterposed ball bearings such as I8; The film 3 in one passage over'shaft I2 is guided between shoulders I9, 20 of and over ders 2|, '22 ofand over rollers I6, I1,

.track of the film past the aperture.

Shaft I3, passing through bearings in panel I, is coupled directly tothe rotor shaft of motor 8. The feeding of the film 'is effected bysprockets such as 23, 24, Figs. 6 and 11, keyed to shaft l3, thesprockets being provided with peripheral teeth as shown for engaging thelateral film perforations. 7

The film strip 3 after leaving reel 4, Fig. 1, passes over a sprocket ofshaft 13 at the left in Fig. 4, thence Fig. 6, it passes between aresilient guide 25 and an idler 26 to the under side of and aroundrollers M, l 5 of shaft I2, Fig. 5, to sprocket 23 on shaft l3, Fig. 6,and back Fig. 11, between resilient guide 2'! and roller 28 to the underside of and around rollers 5, E? of shaft I2, Fig. 5,

to sprocket 24, Fig. 11, over a roller 29, thence under and across andback over a sleeve keyed to shaft I2, Figs. 4 and 5, through the secondsprocket from the left on shaft I3, Fig. 4, to the film rewind reel 5,Fig. 1.

A uniform rate of film feed over rollers I i, I5, IS, IT, irrespectiveof fluctuations in the speed of shaft I3, due for exampleto variationsin the driving torque of motor 8, is secured by making the idlingrollers I4, I5, IS, IT, relatively. massive and by the provision of aviscous packing 3i Fig. 5, such as a high heat grease or the like,filling the space betwen the movable 32 and fixed 33 races for the ballbearings I8. The provision of this viscous packing, which, as stated,constitutes a feature of the invention, has, employed inthe bearinghousings of the relatively heavy idling rollers, proved in practice toafford a highly satisfactory means of maintaining the film feedsufiiciently uniform to eliminate signal distortion'in the process ofscanning.

Referring to Figs. 6, 9, 10, the film perforations are constrained byidling rollers such as 35, 35, to engage the teeth of sprocket 23continuously as the film is fed over the sprocket. To facilitatethreading of the filnnrollers 34, 35, are' the film by the eccentricaction of the, cam. In

order, however, to insure a locking engagement of rollers 34, 35 withthe cam in the position of Fig. 6, the. cam is provided with a notch 43into which a resiliently housed pin or ball bearing 44, Fig. 9, slipswhen the cam is in the locking position. Similar cam and leverarrangements are employed for' disengaging rollers such as 26 from thefilm strip as is illustrated in Figs. 6 and 10. A roller, suchas 44,assists in maintaining the film under constant tension.

As part of the scanning mechanism the cylin drical surface of shaft I2is provided with a pair of axially displaced scanning apertures'45 and46, Fig. 5. Aperture 45 is of a width'sufiicient to embrace the pictureportion 4?, Fig. 4, of the film for scanning; while aperture 56 issufiiciently la'rgeto embrace the sound track 48, Fig. 4. Rollers I4, I5are spaced axially assho-wn suificiently topreventobstructing aperture45 and are so disposed as to guide the picture portion of the film pastthe aperture. Rollers I6, I? are similarly axially spaced sufiicientlyto prevent obstructing aperture 66, and are so disposed with respect tothe aperture as to guide the sound Scanning of the picture portion ofthe film is effected by the optical system illustrated dia- Calgrammatically in Fig. 13, and structurally more particularly in Figs. 6,7 and 8. It employs a light source 49, such as an electric lamp, thefilament of which in series with a variable resistance 55, is energizedfrom a suitable electrical power source connected to terminals 5|. Inits essentials the system comprises the lamp arranged to direct a ribbonbeam through an optical slit 52, normally onto the face of a right prism53, from the hypotenusal face of which the beam is totally reflectedinternally normal y through the third face of the prism onto a lightreflecting and focussing element 54 of a rotary scanning member 55described hereinafter. Element 54 of the scanning member directs andfocusses the beam at the film strip 3, Figs. 5 and 6, as it passes overslot 45. The luminosity of the beam passing through the film isconcentrated by a lens 56, arranged in aperture 45, onto aphoto-electric element 51 disposed within tubular shaft l2 beneathaperture 45.

The scanning member 55 is constructed, as stated, in accordance with theprinciples described in my copending application Serial No. 601,495,filed March 28, 1932. The scanning member, of conical contour, hasdisposed about it at equal inclinations to its axis of rotation, aplurality of scanning elements 45 of identical construction andconfiguration. Each element is a section including the optical axis of aconvex lens and is preferably a section of a hemispherical lens sodisposed on member 55 that the beam reflected from prism 53 impingesnormally on the spherical anterior surface 48 of the lens and thustraverses the lens in a converging radial beam intersecting its opticalaxis at the plane posterior surface which is mirrored over a circulararea 49 for reflecting the entering beam normally back through theanterior surface in a beam converging to a focus at the film strip 3.

Member 55 is mounted on the shaft 60 of a motor 6| having its axis ofrotation situated in a plane substantially perpendicular to the axis ofshafts l2 and I3. Accordingly as member 55 rotates, each lens 54, as itcuts across the beam reflected from prism 53, deflects a focussed imageof an elementary portion thereof transversely across the film strip. Asthe lens in question rotates beyond the luminous field of the beam, thelens next adjacent enters the field and deflects a second beamtransversely of the film, and so on for each succeeding lens.

As these beams move in succession across the film, the film meantime isfed, in the manner described, continuously in a direction at rightangles to the path traversed on the film by the deflected scanning beam.Accordingly the successive scanning beams trace a succession ofcontiguous transverse paths on the film-thereby to scan successivelyevery elementary photographic area thereof.

Photocell 51, thus subjected to a luminous intensity varying frominstant to instant inversely as the opacity of contiguous elementaryareas of the film scanned, translates these luminous intensityvariations into an electrical current varying correspondingly inamplitude.

Lamp 49, optical slit 52, and prism 53 are mounted in alignment on atubular housing 62, Fig. 6, afllxed to a plate 63, Fig. 1, supported bypanel I. Motor 6| is likewise mounted on plate 63. The optical slit isformed by cooperation of a member 64, Figs. 6 and 8, extendinglongitudinally of housing 62, and a transverse member 65 laterally.adjustable to determine the width of the. slit.

The lens elements 54 are aflixed to the scanning member 55 by screws,such as 66, for adjusting the lenses to a proper inclination, afterwhich the lenses are permanentlycemented in place in a suitable medium61. The scanning member is covered by a removable housing 68 providedwith suitable apertures 69, 10 for passage of the scanning beam.

The optical system for scanning the sound track of the film isillustrated schematically in Fig. 13 and structurally in Fig. 12. A beamfrom a source H, such as a lamp connected to terminals 5|, as focussedby a condensing lens 12 at a small slotted aperture of a diaphragm 13. Asecond condensing lens 14 focusses a luminous image of the slottedaperture on the sound track of the film strip 3. The beam transmittedthrough the film is directed through the aperture of a second diaphragm15 disposed in aperture 46 of shaft l2, Fig. 5, onto a secondphotoelectric cell 16 disposed Within tubular shaft l2 adjacentphotocell 54. As the film strip is fed uniformly over idlers l6, I! inthe manner explained, the beam intercepts successive portions of thesound track whereby the current flowing through photocell 16 varies inamplitude in correspondence with the variations in opacity of the soundtrack.

Elements H, 12, 13 and 14 of the optical system are disposed inalignment in a tubular housing 1'. provided with a cover 18 for accessto lamp 1 I. This housing is supported on plate 63, Fig. 1, adjacenthousing 62 of the picture scanning optical system.

Referring to Figs. 2 and 3, the stator housing of motor 8 is rotatablysupported at one end by panel I and at the opposite end by brackets 18secured to the panel. Extending peripherally about the stator are teeth19 meshing with a worm gear 80 keyed to a shaft 8|, actuated by ahandwheel 82. This mechanism provides a means of framing the televisionimage projected on the screen of a receiving system. Rotation of thestator clockwise or counterclockwise by manipulation of wheel 82, framesthe picture up or down as desired.

Meters 83 and 84, Fig. 1, serve to indicate the filament currents oflamps 49 and TI respectively.

I claim:

1. Television apparatus for scanning a strip of motion picture filmcontaining a sound track comprising: a tubular member provided with apair of spaced lateral apertures, means for continuously feeding thepicture portion of said film past one said. aperture and the sound trackpast the other, said means including film idling rollers rotatablysupported on said tube adjacent said apertures, and a, shaft parallelingsaid tube mounting spaced film sprockets whereby said film is fed aplurality of times from said sprocket about said tube, a pair ofphotoelectric elements disposed within said tube, means for directing alight beam through the picture portion of said film and the associatedaperture onto one said photoelectric device, said means including ascanning device for causing said beam to traverse the picture portion ofsaid film in contiguous transverse paths, and means for directing asecond light beam through the sound track portion of said film and theassociated aperture onto the second photoelectric element.

2. In a device for scanning a strip of motion picture film containing asound track: a'tubula r shaft containing a pair of spaced lateralapertures; means for feeding the picture and sound portions'of said filmuniformlypast said apertures 5 respectively, said means including aplurality of axially spaced idling rollers rotatably supported on saidshaft, a driving shaft parallel to said tubular shaft, said drivingshaft having keyed thereto a plurality of film sprockets whereby said'20 tures; means for feeding the picture and sound.

1 track portions of said film uniformly past said aperturesrespectively, said means including a plurality of axially spaced idlingrollers rotatively supported on said shaft, a driving shaft parallel -25to saidtubular'shaft, said driving shaft having a plurality offilmsprockets keyed thereto Whereby said film is fed a plurality oftimes between said driving and said tubular shafts over said sprocketsand idling rollers, a motor directly coupled to saiddriving shaft, andmeans associated respectively with the apertures in said tubular shaftfor scanning the sound track and picture portions of said filmrespectively.

4. In a device for scanning a strip of motion picture film containing asound track: a tubular shaft containing a pairof spaced lateralapertures; means for feeding the picture and sound track portionsof saidfilm uniformlypastrsaid apertures'respectively, said means including aplurality of axially spaced idling rollers rotatively supported 'on saidshaft, a driving shaft parallel to said tubular shaft, said drivingshaft having a plurality of film sprockets keyed thereto whereby saidfilm is fed a plurality of times between said driving and said tubularshafts over said sprockets and idling rollers, a motor directly coupledto said driving shaft, said idling rollers being supported on rollerbearings, a housing for said bearings, a viscous medium retained by saidhousing in contact with said shaft bearings and idling members forproviding a braking eifect during rotation of said idling members, andmeans associated with the apertures in said tubular shaft for scanningthe sound track and picture portion respectively of said film. g i

WILLIAM HOYT PECK.

